This invention relates to a compact integral reciprocating double-acting pump and automatic control valve forming a pumping unit which is powered only by the potential energy of the supply. The pumping unit does not require the installation of a drive pipe for operation.
Similar devices are known but suffer from disadvantage that they require a drive pipe to be installed which needs additional space on site.
An object of this invention is to pump water for domestic use, irrigation, watering stock and other purposes in remote situations when electrical power is not available and the use of fossil-fueled generated power is to be avoided for economic or environmental reasons. Optionally, this type of pump may also be used for water supply wherever an appropriate source of natural energy is available as an alternative to incurring the capital, running, maintenance and depreciation costs of an independent power source.
Accordingly, this invention provides a pumping unit consisting of two high pressure cylinders and a double-acting low pressure cylinder all in-line and an automatic five-port control valve, which can be of the rotary, slide or spool type, operated by a tipping bucket. The tipping bucket is served by a small flow of water bled from the main supply. The power required to operate the pump unit is derived solely from the source of supply water situated at a small elevation above the pump unit.
The frequency of operation of the control valve and thus of the pump may be varied by adjusting the rate of flow of water into the tipping bucket.
The compact unit is enclosed in a single housing and does not require a drive pipe.
The delivery pressure and delivery flow provided by the pump unit is dependent only upon its size and geometry. The operation is automatic and quiet.
Preferably the pumping unit is made of metal or a combination of metal and plastics.